This study will evaluate the effectiveness of Treximet when taken for post traumatic headache by measuring any change in the number of headache days or any change in a subject's ability to think following treatment with study medication. Eligible subjects will complete 3 visits. Following Visit 1, subjects will treat with their usual medication and document headache symptoms and therapy in a Headache Diary. After 30 days, subjects will return for Visit 2 and be randomized (like the flip of a coin) to receive Treximet or matching placebo to treat at the same time each day. Treximet will be provided to treat any headache that occurs. Subjects will complete a daily Diary. After 30 days, subjects will exit the study at Visit 3.